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DC Relay

Hello,

I'm just a complete novice when it comes to building circuitry. The current project I'm working on involves a electronic door strike. The strike requires at least 6vdc to unlock, I'm not sure how many amps right now and I don't have it with me. Given things I can't change, when the door is to be opened I'll have 3.3vdc to trigger the lock. My first thought was just to get a simple relay that will switch the 6vdc when I supply 3.3vdc to the coil of the relay.

So I need a relay w/ a nominal voltage of 6vdc w/ a minimum coil voltage of 3.3vdc. Searching online at RadioHack and Mouser, this seems easier said than found. I've found some that come close. RadioShack part# 275-232 which has a min. switching voltage of 3.5vdc.Same goes for mouser.

So my question is "is there a better way to solve my problem" -- or "could I somehow step up the 3.3v to say 6v and maintain that for at least

5-10 seconds?"

Thanks everyone, Joe

Reply to
Joe Webster
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Hi, Joe. Not quite enough information to work on, but I'm going to assume you're working with a 3.3V logic signal. 3V relays are made, but they usually require more current to drive the coil than a logic signal can provide, and they're not that common. Also assuming the

3.3VDC control signal and the 6VDC-plus power source have the same common, it might be better to use a transistor to turn the lock solenoid on and off (view in fixed font or M$ Notepad): 6VDC Plus o------------o--. 1N5402| | Solenoid - C| ^ C| | C| | | 3.3VDC '--o Control Signal | (1 = ON) ___ |/ o-----|___|-o-| TIP120 4.7K | |>

.-. | | | | 4.7K| | | '-' | GND | | o-----------o---' created by Andy´s ASCII-Circuit v1.24.140803 Beta

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You can get the specified darlington transistor as well as the diode and the rest at Radio Shack or Mouser. This circuit is good for switching up to 1 amp, and 3 amps with a heat sink on the transistor. If you need to switch up to 6 amps, you'll have to replace the diode with a 6 amp diode.

Good luck Chris

Reply to
Chris

"Joe Webster" schreef in bericht news:dKPXd.71602$8a6.24536@trndny09...

Sounds you have a 6V power supply already and I assume it to be powerfull enough to activate the door strike. All you need is a resistor, a transistor and a diode. The transistor needs to be able to handle the current the door strike needs. Use a TIP41 for instance.

+---+--------6V | | | |_ 1N4003 - )| ^ )| door strike | _)| | | +-+-+ | 100_Ohm |/ 3.3V-----|___|-----| TIP41 |>

| | | -----------------+----------- (created by AACircuit v1.28 beta 10/06/04

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petrus bitbyter

Reply to
petrus bitbyter

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It's a bit hard to understand what you are asking but if I have it right, you want a relay with a coil that operates on 3.3vdc to switch a 6vdc supply to the door strike ? Is the "min switching voltage" of the relays mentioned the actual voltage required for the coil ? since a "min switching voltage" sounds a little strange to me. I would be inclined to try one, and mebbe increase the supply volts for the strike too :-)

-- Regards ..... Rheilly Phoull

Reply to
Rheilly Phoull

Try

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Theres everything you need and more there.

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Reply to
Lawrence Oravetz

Joe Webster was thinking very hard :

Sorry that link is

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Reply to
Lawrence Oravetz

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